Field of the Invention
The present invention relates to a semiconductor device, a battery monitoring system, and an address setting method of a semiconductor device.
Description of the Related Art
Conventionally, a so-called daisy-chain connected semiconductor devices have been known in which plural semiconductor devices are connected in series and communicate with one another. Further, systems employing such daisy-chain connected semiconductor devices have been known. For example, a battery monitoring system including a daisy-chain connected semiconductor devices that monitor a battery voltage of a battery cell included in a battery, has been known.
In such a system including the daisy-chain connected semiconductor device, an address value is set for each semiconductor device such that a control section that controls the entire system can recognizes each of the semiconductor devices.
As such method for setting an address value, in each of the semiconductor devices, setting a address value of itself by adding a predetermined value to an address information input from a semiconductor device of a previous stage, outputting the added address value of itself to a semiconductor device of a subsequent stage as the address information (hereinafter, referred to as a “first setting method”), is known. (For example, see Japanese Patent Application Laid-Open (JP-A) No. 2014-49087)
Further, as another method for setting of an address value, in each of the semiconductor devices, setting an address by setting address information input from a semiconductor device of a previous stage as an address value of itself, and outputting a value, obtained by adding a predetermined value to the address value of itself, as address information, to a semiconductor device at a subsequent stage, is known (hereinafter, referred to as a “second setting method”).
Further, as another method for setting an address value, setting an address value by causing a control section, that controls the entire system, to generate the number of address information corresponding to each semiconductor device in the daisy-chain connection, and to output the address information to each of the semiconductor devices, is known (hereinafter, referred to as a “third setting method”).
However, in the first and second setting methods described above, there may be cases in which the address value setting are not accurately performed, due to a gap in a reference clock frequency (deviation in cycle) that serves a reference for performing each operation including generation of the address information, in each of the semiconductor devices. In such cases, for example, an overlapped address value may be set in the semiconductor devices that differ from one another.
Further, in the third setting method described above, a load of the control section increases, since the control section needs to generate the entire address information of the semiconductor devices.